Congressman Ed Markey (D-MA) arrives to meet with House Democrats and U.S. Vice President Joseph Biden about a solution for the ''fiscal cliff'' on Capitol Hill in Washington January 1, 2013.

Credit: Reuters/Joshua Roberts

BOSTON (Reuters) - Democratic Congressman Ed Markey holds a lead over Republican political newcomer Gabriel Gomez in the Massachusetts U.S. Senate race, though a newly released pair of polls differ on how wide his margin is.

A MassInc Polling Group/WBUR poll released on Thursday found that Markey, who has spent more than three decades in the House of Representatives, had the firm support of 41 percent of likely voters, with private equity executive Gabriel Gomez having 35 percent. When undecided voters were pushed to say which candidate they were leaning towards, Markey's lead broadened to 46 percent to 38 percent.

Another poll, by Suffolk University/7 News released late on Wednesday found a wider gap, with Markey holding the support of 52 percent of likely voters, with 35 percent backing Gomez.

The pair, who won their parties' nominations in April 30 primaries, will face off in a June 25 special election to fill the Senate seat that became available when President Barack Obama named John Kerry secretary of state.

The gap between the two poll results likely reflects the fact that not many voters are paying attention to the race, which comes at an unusual time, observers said.

"It's still rather low profile. Lots of folks probably have not made up their minds or really don't intend on voting," said Peter Ubertaccio, a professor of political science at Stonehill College, in Easton, Massachusetts.

Given the low voter engagement, a major part of each candidate's strategy will have to be focusing on getting voters out the door on election day, he said.

"In a special election, off year, during an odd time of the year, your ground game is crucial," Ubertaccio said.

A Gomez victory could help the Republicans retake a majority in the Senate, where they currently have 45 seats. There are 53 Democrats and two independents.

The race is Massachusetts' second off-cycle Senate election in three years; in 2010 voters opted for Republican Scott Brown, who had been a state senator, over Democratic state attorney general Martha Coakley to fill the seat that came open when Democrat Edward Kennedy died. In November, Brown was unseated by Democrat Elizabeth Warren.

Brown's win was unexpected in a liberal-leaning state and left the state's Democratic party to take a more aggressive approach in backing Markey, who declared his interest in the seat in December, even before Kerry stepped down.

"The early perception immediately after the party primaries was that Markey was vulnerable," said David Paleologos, director of the Suffolk University Political Research Center. "These finds suggest the opposite of a close race."

Both polls found that a significant number of voters had not made up their minds about Gomez, the son of Colombian immigrants, with 47 percent in the MassInc poll undecided or unaware of him and 32 percent in the Suffolk poll undecided or unaware.

The MassInc/WBUR poll included 497 likely voters who were questioned on May 5 and 6. The Suffolk/7 News poll counted 500 likely voters from May 4 through May 7. Each has a margin of error of 4.4 percent.